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排序方式: 共有163条查询结果,搜索用时 15 毫秒
141.
OBJECTIVE: We describe two new CT findings of congestive heart failure (CHF): enlarged mediastinal lymph nodes and hazy heterogeneous mediastinal fat. MATERIALS AND METHODS: Forty-six patients were retrospectively identified who had major and minor clinical signs of congestive heart failure and had undergone chest CT during their symptomatic period. Two radiologists reviewed the CT studies and by consensus documented the presence or absence of imaging findings of CHF, including interstitial abnormalities, vascular redistribution, axial thickening, pleural effusions, cardiac enlargement, and mediastinal abnormalities. RESULTS: Smooth septal thickening, bilateral pleural effusions, vascular redistribution, and cardiac enlargement were the most common CT findings in patients with CHF. Enlarged mediastinal lymph nodes and hazy mediastinal fat were seen in 55% and 33% of cases, respectively. In a cohort of 17 patients with elevated pressures in the pulmonary capillary wedge documented within 24 hr of CT, CT scans revealed lymphadenopathy in 14 patients (82%) and inhomogeneous fat in 10 patients (59%). CONCLUSION: Enlarged mediastinal lymph nodes and hazy mediastinal fat occur in patients with CHF and are revealed by CT. Lymphadenopathy in patients with CHF does not necessarily indicate malignancy or an infectious process. 相似文献
142.
The effect of grain source and grain processing on performance of feedlot cattle: a review 总被引:1,自引:0,他引:1
Effects of grain species and grain processing method on DMI, rate and efficiency of gain, and feeding value for cattle fed high concentrate diets were appraised by statistically compiling results from 605 comparisons from feeding trials published in North American journals and experiment station bulletins since 1974. Metabolizable energy (ME) values for each grain and processing method were calculated by quadratic procedures from DMI and animal performance. Averaged across processing methods, ME values for corn, milo, and wheat grain (3.40, 3.22, and 3.46 Mcal/kg DM) fell within 9% of ME estimates from NRC (1996) for beef cattle. In contrast, ME values for barley and oats grain (3.55 and 3.46 Mcal/kg DM) were 24% and 17% greater than NRC (1996) estimates. Compared with the dry rolled forms, high moisture corn and milo resulted in lower ADG and DMI. Compared with dry rolling, either steam rolling or flaking of corn, milo, and wheat decreased DMI without decreasing ADG and improved feed efficiency by 10, 15, and 10%, respectively. Compared with dry rolled grain, steam flaking increased (P < .05) body weight-adjusted ME of corn and milo grain by 15 and 21%, respectively; body weight-adjusted ME for whole corn was 9% greater (P < .05) than for rolled corn grain. Steam flaking was surprisingly effective (13%) at increasing (P < .05) the body weight-adjusted ME of wheat, but steam flaking failed to increase the ME of barley and oats. Higher moisture content of high-moisture corn decreased dry matter intake without depressing ADG and improved efficiency and increased ME of the grain. Compared with steam flakes of moderate thinness, processing milo or barley to a very thin flake tended to reduce ADG and failed to improve feed efficiency. The ideal roughage source and roughage moisture content for maximum ME and ADG varied with grain processing method. Feeding corn silage rather than alfalfa and wet rather than dry roughage depressed (P < .01) ADG of cattle and reduced (P < .01) body weight-adjusted ME of cattle fed high-moisture corn grain but tended to increase both with steam-flaked corn or wheat. 相似文献
143.
FN de Wet JJ Gerber AP L?tter JG van der Watt TG Dekker 《Canadian Metallurgical Quarterly》1998,24(5):447-453
Fanconi anaemia (FA) is an accepted indication for treatment with allogeneic HLA-identical BMT. Most patients, however, lack a suitable HLA-identical donor. In our centre, six FA patients were transplanted with a matched unrelated donor. Due to hypersensitivity to DNA cross-linking agents, a low-dose cyclophosphamide (CY) and thoraco-abdominal irradiation (TAI) regimen is recommended for conditioning in FA. We added Ara-C upfront and anti-T cell antibodies to enhance engraftment and to prevent GVHD, in combination with T cell depletion in four out of six of the first transplants. One patient did not engraft. In three patients rejection was observed. In three of these four patients a second BMT, using full bone marrow grafts, resulted in successful engraftment. The other patient died before a second BMT could be performed. The incidence and severity of acute GVHD was low: only one patient with grade III acute GVHD was seen. Two out of four surviving patients suffered from chronic GVHD. Four patients survived (median survival time 43 months after BMT), three with good and one with acceptable quality of life. Two patients died, one patient due to adenoviral reactivation with multi-organ failure, and one due to sepsis complicated by ARDS. In conclusion, MUD BMT is feasible in FA patients with bone marrow failure in whom no HLA-identical sibling donor is available. In our study group, the major problem was graft rejection, despite the administration of a combination of graft enhancing anti-T cell antibodies. Multicentre studies are needed to determine a more intensive, but still tolerable, conditioning regimen. 相似文献
144.
R Coquard L Ayzac FN Gilly P Romestaing JM Ardiet C Sondaz MP Sotton I Sentenac G Braillon JP Gerard 《Canadian Metallurgical Quarterly》1997,44(3):271-275
Exposure of rats to 2 hours of cold water restraint is associated with both macroscopic and microscopic gastric mucosal injury. Administration of neurotensin into the lateral ventricle or into the nucleus accumbens, one of the mesolimbic dopamine system nuclei, is associated with protection when given before exposure to cold water restraint. Under conditions of cold water restraint, pretreatment with central neurotensin is associated with maintenance of gastric mucosal blood flow and an increase in endogenous gastric mucosal PGE2 activity. In addition, pretreatment with 6-hydroxy dopamine into the mesolimbic nuclei, which depletes them of endogenous dopamine, prior to exposure to cold water restraint, ameliorates the protective effect of central neurotensin. Centrally administered neurotensin inhibits basal, pentagastrin-, carbachol-, and 2-deoxy-D-glucose-induced but not histamine-induced gastric acid secretion. This antisecretory effect is ameliorated by parenteral pretreatment with haloperidol and domperidone. Taken together, these observations support the hypothesis that centrally administered neurotensin, particularly into the nuclei of the mesolimbic dopamine system, confers protection against gastric mucosal injury produced by 2 hours of cold water restraint. This affect may be due, in part, to inhibition of acid secretion and maintenance of mucosal blood flow mediated by an increase in gastric mucosal PGE2 activity. 相似文献
145.
FN Lukash M Schwartz S Grauer F Tuminelli 《Canadian Metallurgical Quarterly》1998,40(4):321-6; discussion 326-7
In 1990, Drs Millard and Latham published their initial experience with dynamic maxillary appliances (DMAs) and periosteoplasty for children with cleft lip and palate. The technique provided for alveolar alignment and consolidation, with elimination of oronasal fistulas. Opponents to this approach speculated about impairments to facial growth. To date no longitudinal studies have been published. Over the last 10 years, 35 unilateral and 10 bilateral complete clefts have been treated with this technique. All patients have been followed and documented clinically, orthodontically, and radiographically. Cephalometric analyses were performed on children after the age of 6 years. The children have excellent facial aesthetics with well-balanced lips and noses. Radiographs demonstrate bone within the repaired alveolar clefts. Articulated impressions show anterior and lateral crossbites in the unilateral patients that improve over time and appear to be correctable orthodontically. The bilateral patients have satisfactory occlusions and arch forms. Cephalometric analyses confirmed no evidence of skeletal crossbites or midfacial growth retardation. This is a work in progress that will continue as the children grow. Although definite and final conclusions would be premature, it can be stated that to date all patients are following consistent and favorable growth patterns. Our team is confident in proceeding with this technique. 相似文献
146.
MF Borgerding JA Bodnar HL Chung PP Mangan CC Morrison CH Risner JC Rogers DF Simmons MS Uhrig FN Wendelboe DE Wingate LS Winkler 《Canadian Metallurgical Quarterly》1998,36(7):169-182
A new-technology cigarette has been developed. While the new cigarette burns some tobacco, it does not use tobacco as the fuel to sustain combustion and provide heat to the cigarette. Rather, the new cigarette primarily heats tobacco thereby reducing products of smoke formation mechanisms such as tobacco combustion, tobacco pyrolysis and pyrosynthesis. The mainstream smoke composition from a cigarette based on the new design (TOB-HT) has been characterized in comparative chemical testing with two reference cigarettes using the FTC puffing regimen. Thermal properties, UV absorption characteristics, elemental composition and materials balance studies all suggest a simplified smoke aerosol. Twenty-five smoke constituents ("target compounds") identified by the scientific community as compounds that may contribute to the diseases statistically associated with smoking have also been measured. Mainstream smoke concentrations of most target compounds are significantly lower with the TOB-HT cigarette when compared with reference cigarettes in the ultra-light "tar" and light "tar" categories. Taken together, chemical analysis results suggest simplified TOB-HT smoke chemistry with marked reductions in specific chemicals reported to be biologically active. 相似文献
147.
JH Vos TS van den Ingh FC Ramaekers RF Molenbeek M de Neijs FN van Mil D Ivanyi 《Canadian Metallurgical Quarterly》1993,30(4):352-361
Eight canine tumors originating from specific glandular structures in the anal region, as well as metastatic tumor tissue of two of these cases (case Nos. 7, 8), were immunohistochemically analyzed using various monoclonal antibodies (MoAbs) directed against human keratin types, vimentin, neurofilament proteins, and alpha-smooth muscle actin. These tumors also were stained for the broad-spectrum neuroendocrine markers neuron-specific enolase (NSE) and synaptophysin. In histologically normal canine anal structures, alpha-smooth muscle actin and NSE antibodies stained basally localized (probably myoepithelial) cells in the anal glands and the anal sac glands. NSE staining also was present in a limited number of luminal cells in both anal glands and anal sac glands. Synaptophysin labeling was not observed in any of these glandular structures. Histologically, the tumors were differentiated into well- and moderately differentiated perianal gland tumors (n = 5) and carcinomas without perianal gland differentiation (n = 3), corresponding to the so-called apocrine carcinomas of the anal region. Immunohistochemically, the perianal gland tumors could be differentiated from the carcinomas by marked differences in staining pattern with the various keratin MoAbs, particularly MoAbs directed against human keratin types 7 and 18. The keratin-staining characteristics of the carcinomas suggest a glandular luminal cell origin. Metastases of the carcinomas showed loss of some keratin-staining characteristics as compared with the primary tumor. Staining for NSE was only observed in solitary cells and small cell clusters in the carcinomas and their metastases, whereas the alpha-smooth muscle actin antibody did not react with the carcinoma cells. None of the tumors stained for neurofilament proteins or synaptophysin. An unequivocal neuroendocrine nature of the carcinomas could not be substantiated by our immunohistochemical study, although the presence of a population of neuroendocrine cells within these neoplasms seems likely. Because the immunohistochemical features of the carcinomas with respect to various keratin MoAbs and NSE are similar to those of the anal glands and the anal sac glands, both these glands might be considered as site of origin of these carcinomas. 相似文献
148.
AA Filaretov LP Filaretova AI Bogdanov FN Makarov EE Granstrem IuI Levkovich NA Mal'tsev 《Canadian Metallurgical Quarterly》1996,82(3):141-150
The influence of stress-induced corticosteroid production on gastric ulceration, blood flow velocity in gastric microvessels and blood pressure was studied in rats. The role of plasma corticosteroids was investigated by means of blockade of the pituitary-adrenocortical system (PACS) and following corticosterone replacement therapy (400 mu/100 g b.w.). The blockade which was induced by Fi. hydrocortisone administration (7 days before stress, 30 mg/100 g b. w.) resulted in an insufficient corticosteroid production. To evaluate the influence of corticosteroids on blood flow velocity in gastric microvessels of muscular, submucosal and mucosal coats it was used intravital microfilming by means of a dark-field contact epiobjective. Stress (water immersion + restraint) induces an ulceration, a decrease in the systemic arterial blood pressure (3 h after stress onset) and a decrease in blood flow velocity in the gastric microvessels (3 h after stress onset). In rats with insufficient corticosteroid production stress-induced ulceration, a decrease in blood pressure and gastric blood velocity were more greater than in rats with intact PACS. Replacement corticosterone therapy corrected all parameters. The results revealed that antiulcerogenic effect of stress-induced glucocorticoid production is realised owing to normalisation of gastric blood supply which is provided by an increase in systemic blood pressure. 相似文献
149.
The effect of moderately high dietary zinc (Zn) on the activities of plasma (PL) ceruloplasmin (CP), and PL and erythrocyte (RBC) copper (Cu), Zn superoxide dismutase (SOD) was determined in weanling rats fed Cu-deficient (DEF; < 1 mg Cu/kg), marginal (MAR; 2 mg Cu/kg), or control (CON; 5 mg Cu/kg) copper diets containing normal or high Zn (HZn; 60 mg/kg) for 4 wk and supplemented with oral Cu (CuS; 5 mg/L) in drinking water for 0, 1, 3, or 7 d. PL Cu decreased (67% compared to CON; p < or = 0.05) in the DEF and increased to control level after 3 d of CuS; increased in the MAR group after 1 d of CuS. HZn reduced overall PL Cu by 27% in all groups, but did not alter the linear increase in PL Cu between 0 and 3 d of Cu S. PL CP activity altered concomitantly with PL Cu levels: The time course of increase in CP activity after 0-3 d of CuS was not influenced by HZn in the diet and CP declined in the DEF group by 92%. There was no correlation between dietary Cu level and PL CP. PL SOD activity decreased by 46% (p < or = .05) in the DEF group, increased to control activity after 1 d of CuS and declined slightly after 7 d; MAR diet did not alter PL SOD. HZn diet increased PL SOD activity in all groups by 150%, reduced activity in the DEF and MAR groups by 65 and 37% and delayed the recovery of PL SOD after CuS. RBC SOD declined in the DEF and MAR groups by 56 and 33% (p < or = 0.05) and did not respond to CuS; HZn diet did not influence RBC SOD activity. These data indicate that moderately high Zn in the diet reduces PL Cu, but not PL CP activity or the recovery of PL Cu or CP activity after oral CuS of Cu-deficient rats, modifies the response of PL SOD to dietary Cu, but does not influence RBC SOD activity. 相似文献
150.
MZ Ozüer FN Ardi? E Coskun AN Yal?in NS Akkoyunlu 《Canadian Metallurgical Quarterly》1999,108(1):87-90
BACKGROUND: Many experts have suggested that blunt splenic trauma in patients older than 55 years should not be managed by observation because of supposed increased fragility of the spleen and decreased physiologic reserve in elderly patients. We sought to determine the outcome of nonoperative management of blunt splenic trauma in patients older than 55 years. METHODS: For the years 1994 through 1996, data for patients with splenic injury older than 55 years from seven trauma centers in a single state were reviewed. RESULTS: Blunt splenic trauma occurred in 41 patients older than 55 years. Eight patients were excluded from further analysis because of death from massive associated injuries within 24 hours of admission. The remaining 33 patients (mean age, 72+/-10 years) were divided into two groups: immediate exploration (10 patients) and observation (23 patients). Observation of blunt splenic injury failed in 4 of 23 patients (17%). No patient deaths were related to the method of management of the splenic injury. CONCLUSIONS: Observation of the elderly patient with blunt splenic trauma has an acceptable failure rate of 17%. 相似文献